The invention relates to a threaded connection for a tubing junction including a threaded part and a matching part fixedly connected with the tube, which embraces the tube externally and rests with an inner surface having grooves at the outer surface of the tube. The fixed connection between the matching part and the tube is produced by rolling material of the tube into the grooves.
A threaded junction of this type is used, for instance, in order to connect hydraulic lines with hydraulic apparatus. Herein the joint between the matching part involved and the hydraulic tube is produced by rolling material of the tube into grooves located on the inside surface of the matching part. These grooves extend in a circumferential direction on the inside surface of the matching part and are closed in themselves. This solution however, fails if the tubing is of a material which does not have the ductility required for the rolling process. In these cases the material of the tubing is excessively deformed, whereby hairline cracks are produced which can be discovered only with very expensive inspection procedures. Furthermore, it was observed that the junctions utilizing tubing material with very high spring back behavior, for instance, titanium do not have the required torsional strength.